Metastasis means that cancer has spread to a different part of your body part than where it started. When this happens, doctors say the cancer has “metastasized.”
The terms "metastatic cancer," "advanced cancer," and "stage 4 cancer" can also be used to describe metastasis, but these terms can have somewhat different meanings. The term advanced cancer can also be used to describe large cancers that have not spread to other parts of the body. If you are unsure, your doctor can help you understand the terms they are using to describe the cancer you have.
How do metastases develop?
Metastases is the plural form of metastasis. Metastases most commonly develop when cancer cells break away from the main tumor and enter the body's bloodstream or lymphatic system. These systems carry fluids around the body. This means that the cancer cells can travel far from the original tumor and form new tumors when they settle and grow in a different part of the body.
Metastases can also develop when cancer cells from the main tumor break off and grow in nearby areas, such as in the liver, lungs, or bones.
Any type of cancer can spread. Whether this happens depends on several factors, including:
The type of cancer
How fast the cancer is growing
Other factors about the behavior of the cancer that your doctor may find
Where can cancer spread?
Cancer can spread to almost every part of the body. However certain cancers are more likely to spread to particular areas. For example, here are some common types of cancer and where they commonly metastasize:
Breast cancer tends to spread to the bones, liver, lungs, chest wall, and brain
Lung cancer tends to spread to the brain, bones, liver, and adrenal glands
Prostate cancer tends to spread to the bones
Colon and rectal cancers tend to spread to the liver and lungs
Less frequently, cancer can spread to the skin, muscle, or other organs in the body.
Cancer cells can also spread to the lining around the lungs called the pleural cavity. It can also spread to the space around the belly called the peritoneal cavity. When these cancer cells cause fluid to build up in these areas, it is called malignant pleural effusion if in the lungs and malignant ascites if in the abdomen.
Is metastasis the same type of cancer as before?
Yes, a cancer that has spread to another area has the same name as the original cancer. For example, a breast cancer that spreads to the liver is called metastatic breast cancer, not liver cancer. This is because the cancer started in the breast and the treatment used is for breast cancer.
How is metastasis diagnosed?
Some people already have metastases when they are first diagnosed with cancer. In this situation, the metastases are usually found during the initial tests to learn more about the cancer.
People can also be diagnosed with metastatic cancer after previously finishing treatment for non-metastatic cancer. As part of a patient's follow-up care plan, one of the main things a doctor will do during these regular check-ups is to look for signs or symptoms that the cancer has come back, called a recurrence. If the cancer has come back and has spread to another part of the body, it is called a metastatic recurrence or a distant recurrence. Specific tests may be done to look for recurrence and metastases.
What are common symptoms of metastasis?
Cancer that has spread may not cause any signs or symptoms. If you do experience any signs or symptoms of metastasis, the type and severity depends on where the cancer has spread.
Cancer that has spread to the bone. Signs and symptoms that cancer has spread to the bone include pain, fractures, bowel and bladder problems, muscle weakness, and hypercalcemia, which is more calcium in the blood than normal. Learn more in this fact sheet (PDF) about cancer that has spread to the bone.
Cancer that has spread to the brain. Signs and symptoms that cancer has spread to the brain include include headache, seizures, dizziness, muscle weakness, balance problems, vision problems, and nausea. Cancer that spreads to the brain can also cause affect how a person's brain processes information, including personality changes, confusion, impaired judgement, memory loss, and socially inappropriate behavior. Learn more in this fact sheet (PDF) about cancer that has spread to the brain.
Cancer that has spread to the liver. Signs and symptoms that cancer has spread to the liver include appetite loss, fatigue, fever, jaundice (high levels of bilirubin cause the skin and whites of the eyes to turn yellow), bloating, and swelling in the legs.
Cancer that has spread to the lungs. Signs and symptoms that cancer has spread to the lungs include coughing, coughing up blood, chest pain, breathing problems, and fluid around the lungs.
Contact your health care team if you experience any of the symptoms above. These can be signs of cancer metastasis or another health problem. Your health care team may want to do specific tests to learn more about the cause of your problem and find how to best treat it.
How is metastasis treated?
Treatment depends on:
The original cancer and where it started
How much the cancer has spread and where it is located
Your age and health
Your personal treatment choices
Researchers are constantly working to learn more about how metastases may differ from the original tumor at the molecular and genetic level. This is why treatment for metastasis can be different from the treatment used for the original tumor.
Treatment may include chemotherapy, immunotherapy, targeted therapy, or hormone therapy. Surgery and radiation therapy may also be options for some types of metastatic cancer. Doctors might try one type of treatment and then switch to another when the first treatment no longer works. Or you might have a combination of treatments. Learn more about the types of treatments for specific cancers in another section of this website.
Does treatment cure metastatic cancer?
In some situations, metastatic cancer can be cured. But for most metastatic cancers, treatment does not cure the cancer but it can slow its growth and reduce symptoms. It is possible to live for many months or years with certain types of cancer, even after the development of metastatic disease.
How well any treatment works depends on:
The type of cancer
How far the cancer has spread and where it is located
How much cancer there is
If the cancer is growing quickly or slowly
The specific treatment
How the cancer responds to treatment
It is important to ask your doctor about the goals of your treatment plan. These goals may change during your care, depending on whether the cancer responds to treatment.
It is also important to know that pain, nausea, and other side effects can often be managed with the help of your health care team. This is called palliative care and should be a part of any treatment plan, regardless of the type or stage of disease. Let your cancer care team know when you experience side effects so they can help provide relief. Research shows that palliative care can improve the quality of your life and help you feel more satisfied with the treatment you receive. Learn more about palliative care, also called supportive care.
Are there clinical trials for metastatic cancer?
Yes. Clinical trials are research studies that are investigating treatments that are not yet available to the public. Clinical trials are the main way doctors find new and effective treatments for cancer, including metastatic cancer. A clinical trial might be the main treatment approach for metastases, or just one of the options. Learn more about clinical trials and talk with your health care team about what clinical trials may be open to you.
Living with metastatic cancer
When you live with cancer for many months or years, many people think of it like a chronic, or long-term, illness. Like someone with any chronic illness – such as diabetes or heart problems – getting this ongoing medical care and treatment is crucial. This can also be called "extended treatment."
Be sure to follow your extended treatment plan so it works as well as possible. It is also important to get the support you need for the physical, emotional, and social effects of living with cancer. Learn more about living with chronic cancer.
Questions to ask the health care team about cancer metastasis
Consider asking your health care team the following questions. The first set of questions is about your risk of metastases, and the second set may be helpful if you've received a diagnosis of metastatic cancer.
Where does this type of cancer typically spread?
How likely is it that the cancer could come back and spread?
What are the signs and symptoms of metastasis that I should look out for?
How often should I see the doctor as part of my follow-up care?
If I am concerned about a new symptom or sign, who should I tell? How soon?
If I'm very worried about the cancer coming back and spreading, who can I talk with?
If I have been diagnosed with metastatic cancer, what treatment plan do you recommend?
Should I get a second opinion? Who would you recommend?
What are the goals of each treatment in the plan? Is it to eliminate the cancer, help me feel better, or both?
What clinical trials are open to me? How can I learn more about them?
What support services are available to me? To my family?
Dealing with Cancer Recurrence
Understanding Statistics Used to Guide Prognosis and Evaluate Treatment
National Cancer Institute: Metastatic Cancer
American Cancer Society: Advanced Cancer, Metastatic Cancer, and Bone Metastasis